Slide valve controlled pneumatic weft holding device



June 13, 1967 w RAWER 3,324,8 7

SLIDE VALVE CONTROLLED PNEUMATIC WEF'P HOLDING DEVICE Filed May 18, 19652 Sheets-Sheet l INVENTOR WALTER RAiNER Rodi june H3, 3967 w. RAENER 3 3SLIDE VALVE CUNTROLLED PNEUMATIC WEF'I HOLDING DEVICE Filed May 18, 19652 Sheets-Sheet 2 INVENTOQ WA LTER WAINER United States l at'ent 6 3324,897 SLIDE VALVE CONTliQLLElD PNEUMATIC WEFT HOLDINGDEVICE WalterRainer, Dornhirn, Vorarlherg, Austria, assignor to Adolph Saurer Ltd,Arbon, Switzerland Filed May 18, 1965, Ser. No. 456,724 Claims priority,application Austria, May 21, 1964, A 4,417/64 2 Claims. (Cl. 139170.3)

This invention relates to looms, and more particularly to weft holdingmeans for use on drop box looms and the like. I

Looms provided with shuttle changing mechanism such as drop boxes arecontrolled by pattern cards to convey into the plane of the lay theparticular shuttle compartment which contains the shuttle for thedesired color. Shuttle changing mechanisms of this kind are known to besubject to the serious problem that especially at the time of shuttlechange, the several wefts become entangled, with the result that onpicking, not only the weft conveyed into the plane of the lay isintroduced into the web, but also wefts deriving from adjacent,supposedly inactivated shuttles are introduced to create entanglement.These stray wefts must thereafter be removed which necessitates atroublesome and time consuming operation. The provision of a drop boxloom free from this grave drawback, therefore, has long been adesideratum in this art a long time.

A promising approach to a solution of this problem 1s provided by thepresent invention in a pneumatic devlce which includes suction portsdisposed in the shuttle compartments on the side of the box facing thelay, and wherein the conduits leading to the individual ports originatedat individual openings are arranged in a vacuum distribution chamber.This pneumatic device is designed to maintain the wcfts extending fromthe shuttle compartments to the web, under tension, so that a mutualentanglement of the wefts in this region is effectively avoided. Whileon the whole satisfactory, this arrangement suffers from thedisadvantage that inasmuch as the suction effect is imparted to andmaintained at all the suction ports at all times, a very materialsuction output is required which can be delivered only by a powerful andhence, costly, vacuum pump.

It is a principal object of the invention to provide a device forpreventing weft entanglement as encountered in shuttle changing drop boxlooms, which, while utilizing a pneumatic principle as proposed in theprior art, materially improves the known system by materially reducingthe size and cost of the vacuum installation required.

Other objects, and the manner in which the same are attained, willbecome apparent as this specification proceeds.

In implementation of the afore-noted objective, the present inventioncontemplates providing the vacuum distribution chamber of a shuttlechanging drop box loom with a distributor valve arranged in said chamberfor displacement relative thereto, and designed to close certainopenings of the distributor chamber in accordance with the position ofthe drop box relative to the plane of the lay.

The invention is based on the discovery that without impairing in theleast the efiiciency of the pneumatic system, some of the suction portson the drop box may be closed, so as to afford a very material saving inthe pump capacity required, the choice of the ports thus closed beingdictated by the position of the drop box relative to the lay. Suctionports which can always be closed are the ports in the shuttlecompartment which is disposed in the plane of the lay.

The preferred embodiment of the invent-ion includes upper and lowersuction ports, preferably disposed in the side wall, for each shuttlecompartment; the upper port may be omitted in the top compartment, andthe lower port may be dispensed within the bottom compartment. I havefound that dependent on the position of the drop box relative to thelay, only one of the pair of ports in each shuttle compartment isactually needed to hold and maintain under tension, the weft derivingfrom the shuttle in the compartment. More particularly, I have foundthat the only suction ports which are required to be operational, i.e.which must be connected with the pump so as to function as an active,elfective suction means, are the lower suction ports of the compartmentsdisposed above the plane of the lay, and the upper suction ports of thecompartments disposed below the plane of the lay. The remaining suctionports may be shut oil? from the source of vacuum whereby the suctionoutput required is very materially reduced.

This selective shut-off or closing of part of the suction ports of ashuttle changing drop box loom is achieved, according to the presentinvention, by providing the vacuum distribution chamber with openingswhich are spaced from one another by the same distance, a suctionconduit leading from each of said openings to one of the suction portsin the shuttle compartments of the drop box of the loom, and byproviding a distributor valve arranged for displacement relative to thevacuum distributor chamber, this valve having openings which in thecenter are spaced from one another by three times the distance betweenthe openings in the distributor chamber, and which above and below thecenter are mutually spaced by twice the distance between the openings inthe distributor chamber.

Above and below the center where the distance between two valve openingsis three times the distance between openings in the distributor chamber,the distributor valve should have n/2 valve openings if n represents thenumber of openings in the vacuum distribution chamber.

The vacuum distributor chamber may be mounted on the drop box, and thedistributor slide valve on the bearing for the drop box whichis mountedon the loom.

In this manner, the displacement of the distributor valve relative tothe openings in the distributor chamber, which is essential foreffective control purposes, is effected automatically so that there isno need for any ancillary driving mechanism. The same advantage issecured, of course, if the arrangement is reversed and the distributorvalve is mounted on the drop box, and the distributor chamber on theloom-mounted bearing for the drop box, the former arrangement, however,being preferred as it is the simpler one of the two constructions.

In the drawings accompanying this specification and forming partthereof, a preferred embodiment of the invention is illustrateddiagrammatically by way of ex ample, and without any limitative intent.

In the drawings:

FIG. 1 illustrates schematically the drop box of a shuttle changing loomas seen from the side opposite to the operators station;

FIG. 2 is a similar schematic side view of the same drop box, viewed,however, from the operators station;

FIG. 3 is a longitudinal section on an enlarged scale, of the vacuumdistributor chamber and distributor valve associated with the drop boxof FIGS. 1 and 2, and

FIG. 4 shows, on a still further enlarged scale, a section taken alongline IV-IV in FIG. 3.

Referring to the drawings wherein like elements are denoted by identicalreference numerals, the drop box 1 which is disposed on the side of thelay (not shown in the drawings) comprises six shuttle compartments 2 2 22 2 and 2 The drop box 1 is mounted on a shaft 3 which is disposed forvertical displacement in a bearing 15 which is mounted on the loom (notshown in the drawing). By suitable control of the stroke of the shaft 3,and thus, the vertical displacement of the drop box 1, any one of theshuttle compartments 2 2 can be placed in the plane 4 of the lay.Picking is effected by causing a picking means (not shown in thedrawing) to hit the shuttle in that compartment which is disposed in theplane 4 of the lay, and to throw the same through the shed into the boxprovided on the other side of the lay, the surface of the lay serving asthe race.

As seen particularly in FIG. 1, the drawings illustrate the position inwhich the shuttle compartment 2 is situated in the plane 4 of the lay.The shuttle originally contained in the compartment 2 has been ejectedfrom the compartment and is now located in the shed or in the box on theother side of the lay. The remaining shuttles 5 have remained in theircompartments and are inactive. The wefts 6 deriving from theseremaining, inactive shuttles 5 extend between the selvedge 7 and theexit for the weft on the respective inactive shuttle 5.

The pneumatic suction device with which the loom is equipped, comprisesessentially a distribution chamber 8 mounted on the drop box 1, asuction manifold leading to the suction pump (not shown in the drawingand suction conduits 10 which lead from the distributor chamber 8 to thesuction ports 11. The suction ports 11 are arranged in the side wall ofthe drop box 1 facing the operators station and in the vicinitcy of theopenings facing the lay, of the shuttle compartments 2 2 and this insuch a manner that shuttle compartments 2 2 2 and 2 are provided withtwo suction ports 11an upper port and a lower port-for each compartment,while the uppermost shuttle compartment 2 has only a lower suction port,and the lowermost shuttle compartment 2 has only an upper suction port.

Under the influence of suction, the wefts 6 deriving from shuttles 5 arepulled toward the ports 11 and thus, held tight over the entire distancebetween selvedge 7 and the weft exit of every shuttle 5; manifestly,this arrangement prevents the wefts 6 deriving from the inactiveshuttles 5 from becoming entangled and from being carried along by theshuttle moving across the lay.

It is apparent from the drawing, and particularly from FIG. 1, that inall compartments containing an inactive shuttle, i.e. in compartments 22 2 2 and 2 only one of the suction ports 11 is effective in holding bysuc tion, the weft 6 passing across such port, while the other one ofthe pair of ports 11 provided in each compartment is disposed remotefrom the path of the weft 6 and hence, is not effective in holding thisweft; when it comes to the compartment, 2 the shuttle of which has beenejected from the compartment to proceed in the plane 4 of the lay, bothsuction ports 11 may be inactivated as neither is called upon to act onany weft 6. In accordance with the invention, those ports which are notneeded for holding any weft 6, are shut off from the source of vacuumwhereby the overall suction output, and therefore also the cost of theinstallation and operation of the suction system, are very materiallyreduced. The selective shut-off of all those suction ports which at anygiven point of operation of the shuttle changing device, are not neededfor weft holding purposes, is effected, in accordance with the presentinvention, by a control organ which will now be described.

According to the preferred embodiment of the invention illustrated inthe drawing, this control organ is provided in the form of a flatdistributing slide valve 12 which is arranged in the distributor chamber8, for sliding displacement along a series of apertures 13 13 13 13 1313 13 13 13 and 13 which open into the suction conduits 10, and whichare spaced from one another by one and the same distance. Thedistributing slide valve 12 is provided with a series of openings 14 1414 14 14 14 14", 14 14 and 14 which are also mutually spaced, thedistance between the openings 14 14 varying, however, in the followingmanner. The openings 14 and 14 are spaced by a distance which equalsthree times the spacing between adjacent openings of the series 13 13 ofthe distributor chamber 8; for adjacent ones of the remaining openings14 14 and 14 14 the spacing is always twice the distance betweenadjacent openings of the 13 13 series.

The distributing slide valve 12 is mounted on the bearing 15 of the dropbox 1 on the loom. The distributing slide valve 12, therefore, does notpartake of the color change strokes of the drop box 1. Dependent on theposition of the drop box 1 relative to the plane 4 of the lay, i.e.dependent on which of thte shuttle compartments 2 2 happens to bedisposed in the plane of the lay, the distributing slide valve 12assumes a predetermined position relative to the series of openings 13:13 on the distributor chamber 8, which causes quite some of theseopenings 13 13 to be covered up. Only those openings 13 13 are kept openby the valve openings 14 14 which by suction conduits 10 are connectedwith those suction ports 11 which are absolutely required to beoperational, i.e. which are needed for holding wefts 6 by the force ofsuction. Covered up, therefore, are those among openings 13 13 which arecorrelated with (a) both the suction ports 11 of the shuttle compartmentwhich is disposed in the plane of the lay, (b) the lower suction portsof the shuttle compartments disposed below the plane of the lay, and (c)the upper suction ports of the shuttle compartments disposed above theplane of the lay.

FIG. 3 shows a position of the distributing slide valve corresponding tothe position of the drop box as illustrated in FIGS. 1 and 2. As thedrop box 1 rises or descends, the distributor chamber 8 including theseries of openings 13 13 rises and descends correspondingly, and thedistributing slide valve assumes an ever varying position relative tothe series of openings 13 13 this position always corresponds, however,to the control scheme described above.

The distributing slide valve 12 is guided, as illustrated in FIG. 4, inthe dovetailed groove of a rail 16. Guide and packing members 17 aremounted at the top and bottom points of exit of the slide valve from thedistributor chamber 8. The upper packing member can be disposed with ifthe chamber 8 is sufliciently extended upwardly.

The flat side valve 12 shown in the drawings, may be replaced by acircular slide valve with valve openings which like a rotary piston, isarranged in a cylinder, the rotary piston being activated from the driveshaft effecting the upward and downward displacement of the drop box andthe cylinder assuming the function of the vacuum distributor chamber.

I wish it to be understood that I do not desire to be limited to theexact details of construction, design and operation shown and described,as modifications within the scope of the claims following below, andinvolving no departure from the spirit of the invention nor anysacrifice of the advantage thereof, may occur to persons skilled in theart.

Iclaim:

1. In a loom including a drop box, a pneumatic weft holding device,compartments in said drop box which open in the direction of the lay,suction ports in the side wall of said drop box which are adjacent saidcompartment openings, a vacuum distributor chamber for said pneumaticweft holding device, said vacuum distributor chamber having a pluralityof equally spaced apart openings which connect to a plurality ofcorresponding suction conduits leading from said vacuum distributorchamber to said suction ports in said drop box, the improvement which,comprises a distributing slide valve arranged in said vacuum distributorchamber for displacement along said openings in said distributorchamber, said slide valve having openings which are spaced from oneanother at the center of the valve by three times the distance betweenadjacent openings in the distributor chamber and above and below thecenter of the valve by twice the distance between adjacent openings inthe distributor chamber to adapt the slide valve to selectively closesome of said openings in said vacuum distributor chamber in response tothe prevailing position of the drop box relative to the lay.

2. The combination as claimed in claim 1, wherein said vacuumdistributor chamber is mounted on said drop box and said distributingslide valve is mounted by bearing means on the loom, said bearing meansalso mounting said drop box on the loom.

References Cited UNITED STATES PATENTS 2,762,399 9/1956 Moseley et a1139-170.3 2,842,164 7/1958 Head 139-170.3 3,186,444 6/1965 Schaifer139-194 X 3,238,976 3/1966 Rainer 139170.3

OTHER REFERENCES Samar-Pneumatic Weft Separator, 1 sheet received June3, 1964.

MERVIN STEIN, Primary Examiner.

15 I. KEECHI, Assistant Examiner.

1. IN A LOOM INCLUDING A DROP BOX, A PNEUMATIC WEFT HOLDING DEVICE,COMPARTMENTS IN SAID DROP BOX WHICH OPEN IN THE DIRECTION OF THE LAY,SUCTION PORTS IN THE SIDE WALL OF SAID DROP BOX WHICH ARE ADJACENT SAIDCOMPARTMENT OPENINGS, A VACUUM DISTRIBUTOR CHAMBER FOR SAID PNEUMATICWEFT HOLDING DEVICE, SAID VACUUM DISTRIBUTOR CHAMBER HAVING A PLURALITYOF EQUALLY SPACED APART OPENINGS WHICH CONNECT TO A PLURALITY OFCORRESPONDING SUCTION CONDUITS LEADING FROM SAID VACUUM DISTRIBUTORCHAMBER TO SAID SUCTION PORTS IN SAID DROP BOX, THE IMPROVEMENT WHICHCOMPRISES A DISTRIBUTING SLIDE VALVE ARRANGED IN SAID VACUUM DISTRIBUTORCHAMBER FOR DISPLACEMENT ALONG SAID OPENINGS IN SAID DISTRIBUTORCHAMBER, SAID SLIDE VALVE HAVING OPENINGS WHICH ARE SPACED FROM ONEANOTHER AT THE CENTER OF THE VALVE BY THREE TIMES THE DISTANCE BETWEENADJACENT OPENINGS IN THE DISTRIBUTOR CHAMBER AND ABOVE AND BELOW THECENTER OF THE VALVE BY TWICE THE DISTANCE BETWEEN ADJACENT OPENINGS INTHE DISTRIBUTOR CHAMBER TO ADAPT THE SLIDE VALVE TO SELECTIVELY CLOSESOME OF SAID OPENINGS IN SAID VACUUM DISTRIBUTOR CHAMBER IN RESPONSE TOTHE PREVAILING POSITION OF THE DROP BOX RELATIVE TO THE LAY.